This invention relates to flexible couplings for joining two rotatable shafts or other rotatable parts which may have their axes misaligned, and deals more particularly with such a coupling using as the principal connecting element a simple, easily manufactured flex member.
Flexible couplings are commonly used in rotary power transmitting systems for drivingly joining two rotatable parts in cases where it is difficult to precisely align the axes of such parts, where the axes of such parts tend to move or shift relative to one another during operation of the system, or where a misalignment of the axes is intentionally included in the design of the system. One form of misalignment is parallel misalignment wherein the axes of the driving and driven members are parallel to one another in at least one plane but do not intersect. Another form of misalignment is angular misalignment in which the two axes may intersect, but in one plane are at an angle of other than 180 degrees to one another. Still another form of misalignment is endwise misalignment which occurs when one or the other of the driving and driven members moves along its axis to cause the two members to move toward or away from one another.
The general object of this invention is to provide an improved flexible coupling capable of handling relatively large amounts of angular misalignment. More particularly, it is intended to provide a flexible coupling which may be used in many applications where Hooke's or universal joint couplings have conventionally been used in the past to join two drive shafts or the like having their axes positioned at an angle to one another.
A further object of the invention is to provide a flexible coupling of the foregoing character which has a substantially constant angular velocity across the coupling so as to avoid vibratory forces such as generated by conventional Hooke's joint couplings.
Another object of the invention is to provide a flexible coupling which has no relatively sliding parts subject to wear and which coupling, therefore, requires no lubrication and has a long service life.
A still further object of the invention is to provide a flexible coupling which may be readily designed to provide for a shear disconnect, that is it may be made so as to be disconnectible and movable sideways from the driving and driven parts which it joins without disturbing such parts or their supporting bearings. Further, the coupling is one in which there are no hidden surfaces and, therefore, on inspection of the coupling all incipient cracks or other manifestations of potential failure are readily visible.
Prior art U.S. Pat. No. 3,625,024 shows a coupling having a connecting member with some similarity to the flex member of this invention. However, the coupling of said patent is intended primarily to accommodate parallel misalignment and has the arms of its connecting member designed to pivot or bend in the plane of the member. The arms are not designed to bend out of the plane of the connecting member as are the arms of the flex member of this invention.
Other objects and advantages of the invention will be apparent from the drawings and from the following detailed description of the preferred embodiments.